It is actually painful to watch this guy tear into a cart, just not necessary.
All that is needed is a syringe and you pull out 60ml at a time to insert in your refillables. Then you leave the cart intact, much cleaner.
No need to store the unused portion. You also can keep track of the ink date at the same time.
Have been doing this with K3 inks for 5 years for my 9900,9890 and 3880 and have over 10,000 ml on hand.
The main reason I had my 9900 repaired with a new head. Wanted to stay K3.